1. Field of the Invention
The present invention relates to a quartz probe apparatus, and more particularly, to a quartz probe apparatus capable of being easily aligned with an object of examination.
2. Description of the Related Art
A number of electrode pads are formed on a semiconductor device, such as an IC, and a probe apparatus is used to examine the electrical properties of the semiconductor device. A wafer probe apparatus is also used for testing the electrical properties of the semiconductor device in the form of a wafer. In this probe apparatus, a number of microprobes are arranged corresponding to the electrode pad arrays of the semiconductor device, on an insulated substrate. A probe card is conventionally used for the examination (Published Examined Japanese Patent Application Nos. 54-43354, 58-32782, etc.). In this probe card, a number of microprobes are fixedy arranged at fine pit.ches on an insulated support so that the microprobes can be in contact with a number of electrode pads formed at the peripheral portion (usually, four sides) of an IC.
Conventionally, however, the microprobes are manually arranged on the insulated support, and this manual work is very troublesome. Lately, the technology for fine processing of the semiconductor device has advanced, and accordingly the degree of integration of a semiconductor device has improved. For example, some hundred IC chips are formed on a 6 inches semiconductor wafer. The size of a chip is as large as 5 square mm, and a row of some hundred electrode pads is formed on each side of a chip. As the degree of integration of a semiconductor device improves, the number of the electrode pads increases, accordingly. Thus recently, electrode pads having the size of 60 square .mu.m to 80 square .mu.m are arranged on a side of a chip with an arrangement pitch of 20 to 50 .mu.m. Some hundred microprobes which the diameter of each distal end is 30 .mu.m, need to be simultaneously brought into contact wit electrode pads such as above.
Meanwhile, tungsten probes for use as conventional microprobes are manufactured by drawing tungsten. Currently, therefore, the diameter of tungsten can be reduced at most to 100 .mu.m.phi.. Consequently, in the case where tungsten is used as the microprobes, the diameter is wider than 100 .mu.m.phi.. Thus, the microprobes manufactured by the conventional method cannot cope with the demand for higher-density semiconductors.
A quartz probe apparatus is a promising probe card of a new type. It is manufactured using the IC manufacturing technique which enables fine processing. According to this method, a quartz plate is etched to form a number of fine-pitch microprobes and electrodes simultaneously. Quartz is selected as the material of the microprobes for the following reasons.
(1) Since quartz permits anisotropic etching, overetching and side etching can be minimized.
(2) Since the technique used is established in the manufacture of vibrators, the production is steady.
(3) Since quartz has a high modulus of elasticity, it can absorb the unevenness of the electrode pads.
(4) Since quartz has a constant modulus of elasticity, the microprobes suffer less fatigue after repeated use.
In the conventional method for manufacturing the quartz probe apparatus, a plurality of probe bodies, which correspond individually to electrode pads arranged along one side of an IC, are formed on one quartz plate by etching. FIG. 1 is a plan view of the quartz plate on which the probe bodies are formed. In FIG. 1, numeral 1 denotes the quartz plate. Probe bodies 2 and 3 of different sizes are formed by etching quartz plate 1. Prob bodies 2 and 3 include microprobe portions 2a and 3a having a number of microprobes of fine pitches in contact with the electrode pads of the IC, electrode pad portions 2b and 3b formed on the other end side of bodies 2 and 3, and wiring pattern portions 2c and 3c connecting microprobe portions 2a and 3a and electrode pad portions 2b and 3b, respectively. The respective longitudinal straight portions of microprobe portions 2a and 3a and electrode pad portions 2b and 3b extend along the crystal axis of Y-axis of quartz plate 1.
Subsequently, a metal pattern layer is formed on each of probe bodies 2 and 3. Thereafter, probe bodies 2 or 3 of the same type are combined in sets of four, and each set is fixed to a mother board (not shown). In fixing the probe bodies to the mother board, the probe bodies are accurately aligned so that their respective microprobes ar individually in contact with the electrode pads of the IC.
Thus, according to the quartz probe apparatus described above, the fine-pitch arrangement of the microprobe portions can be achieved with ease. The high-accuracy alignment work, however, requires much time and labor.